Improvement in valves and valve-gears



ETERS. FNOTQLITHOGRAPHER, WASHINGTON D C NUNITED 'IArns {AHI'N wILLIAMZ. HAroHnn, or PLYMOUTH, PENNSYLVANIA, AssIeNon To HIMsnLr AND WILLIAML. LANGE, on sAMn rLAcn.

IMPROVEMENT IN VALVES AND VALVE-GEARS.

Specification forming part of Letters Patent N0. 1&3A2S, dated April 4,1871.

have invented an Improved Valve and Valve- Motion for Steam-Engines, ofwhich the following is a specification:

Nature uml Object of' the Intention.

My invention consists of the combination, with a steam-cylinder andpiston, of a valve operated, substantially in the manner describedhereafter partly by the positive motion of the piston and partly by thedirect action of the steam also, of the combination, describedhereafter, of a grooved cylindrical valve with certain steam and exhaustports.

The object of my invention is to obtain such a rapid reciprocatingmotion of the piston without the aid of the usual eccentric or crank foroperating the valve that the engine may be applied directly to theoperating of pumps, blowing-cylinders, and especially to rock or coaldrills.

Description of thc Accompanying Drawing.

Figure 1 represents a longitudinal section of cylinder and valve-chestwith my improved valve-motion; Fig. 2, a transverse section of the sameon the line l 2, Fig. l; Fig. 3, a transverse section on the line 3 4,Fig. l; and Fig. 4, a sectional plan view of the valve-chest on the line5 `(j, Fig. 1.

General Description. A represents a steam-cylinder, and B its piston,the rods a a of the latter projecting tained in an elongated slot in thespindle E of l the valve, and which can be either adjustable or not, thedistance between the peripheries of the two rollers being greater thanthe width of the arm, for a purpose rendered apparent hereafter. Y

Fis a cylindrical valve, arranged to slide in a cylindrical chamberformed in the valvechest G, in which, above the valve, is alongitudinalpassage, m, steam from the generator being admitted to this passage,which communicates.through ports 7L h with the in.- terior of thevalve-chest at one end of the same, and `through ports h1 h1 with theopposite end of the said valvechest. It will be observed, on referenceto Figs. 3 and 4, that these steam-ports h h and hl lil communicate atpoints directly opposite to each other with the interior of thevalve-chest, so that, the pressure of steam from the ports being equalon both sides of thevalvc, the latter will be equally balanced, and willwork Inuch more freely than if the steam were admitted at one pointOnly. Portions only of the steam-ports g and g are opposite to theVports h h and hl.

h1, as will be observed on reference to Figs. 1 and 4.

The exhaust-ports p p communicate, during a portion of the stroke of thevalve, with annular grooves w fw cut in the said valve, the steamescaping through a suitable opening or openings in the side of thesteam-chest.

The operation ofthe valve is as follows: When the piston has very nearlyreached the limit of its stroke in the directionof the arrow the arm h3strikes the roller t" of the valvespindle, and so moves the valve as tocover theeXhaust-port p and steam-ports h1 h, halfopen the steam-port q,and very slightly open the steam-ports It h and exhaust-port p. Thispartial movement of the valve is all the duty which the arm h has toperform, the further movement of the valve being accomplished by thepressure of steam against the rear end, w, of the valve, which causesthe latter to move suddenly, and t-hus flirt-her` and fully opens thesteam-ports L h and brings the annular groove w opposite the exhaustportp', thereby insuring a free escape of the exhaust-steam at the front endof the cylinder through the passages t p w', while a full volume of livesteam is introduced at the rear end of the same through the passages qt.

The result of the above movement of the valve is the instant reversal ofthe piston, and as the latter reaches the limit of its forward movementthe arm h3 strikes the rollerz' of the 2 nadas valve-spindle, andthereby slightly moves the valve, so as to close the steam-ports h 71partly close the port q, and slightly open the exhaustport p andsteam-ports h1 h1, the completion of the valve movement being effectedby the pressure of steam against its end y, and the movement of thepiston being again reversed.

To increase or diminish the stroke of the valveitis onlynecessary tolengthen or shorten the operating-arm h3 by a proper vertical adjustmentof the pin c, or to adjustthe rollers c' t" from or toward each other.(See Fig. l.)

It will be thus seen that the necessary movement of the valve to cause areciprocating movement of the piston is accomplished partly by apositive motion derived from the pistonrod andpartly by the pressure ofsteam against the valve itself.

Although the movements of the valve are sudden, it is relieved at everystroke from jars or shocks by a cushion of steam between the end of thechamber of the valve-chest and the end of the valve opposite to that onwhich the live steam is acting.

Although the above-described valve-motion is applicable topumping-engines and blowingengines, it has been more especially designedfor rock or coal drills, inwhich the drillingtool is secured directly tothe piston-rod.

Y It Will be seen that as the direct or live steam from the boilerpasses to the ends of the valve F, the latter will not be balanced underany circumstances, so that the steam can act with its full force uponthe valve, the rapid positive movement of which is thus insured.

Claims.

1. The combination, with a steam cylinder and piston, of a valve, F, anddevices, substantially as described, whereby the valve is operatedpartly by a positive movementl derived from the piston and partly by theaction of steam passing directly from the boiler.

2. rlhe ports q q', p p', and h h1, arrangedin respect to the grooves inthe valve F, as described.

3. The ports h h h1 h1, arranged in relation to the valve F, coveringsaid ports, and communicatin g with the interiorof the valve-chest,substantially as described.

4. The arrangement of the ports h h1 in respectl to the ports q q and tothe valve F, as and for the purpose specified.

In testimony whereof I have signed my name to this specication in thepresence of two subscribing witnesses.

WILLIAM Z. HATCHER.

Witnesses:

HARRY SMITH, WM. A. STEEL.

